British Counter-Intelligence Against Subversion in the 1930s

Introduction and Historical Background

The period between the two World Wars was a time of acute confrontation between national intelligence and counter-intelligence agencies, particularly across Europe. The extent to which such agencies managed to address those challenges to the benefit of their own governments remains a subject of debate among analysts and experts to this day. An important case study is the role of intelligence — and counter-intelligence in particular — in the United Kingdom during the inter-war period. This paper assesses the degree to which MI5 and MI6 succeeded in deterring and countering the left- and right-wing threats emanating from the Continent. Given the tumultuous historical context and the level of development of information-gathering techniques at the time, British counter-intelligence managed to deter most Soviet, Nazi, and Fascist influences during the period in question. However, taking into account the events of the Second World War and the subsequent Cold War, it can be concluded that not all challenges were adequately met, and the role and actions of the agencies should have been more substantial.

The research focuses on several key aspects. First, understanding the historical background of the inter-war period — with its doctrinal influences and political stakes — is essential for contextualizing the work of the counter-intelligence agencies. Second, the role of counter-intelligence as a modus operandi in national and international politics helps clarify the precise position of MI5 and MI6 within the broader intelligence framework. Third, examining the agencies' activities and their respective successes and failures in countering domestic and international doctrinal threats illuminates the capacity of the British state to resist left- and right-wing influences. Finally, the conclusion identifies both the achievements and the shortcomings of the British agencies in deterring Russian, German, and Italian intelligence operations.

The historical background of the 1930s was profoundly shaped by the outcome of the First World War. The end of the war, with the demise of the European empires — and the Russian Empire in particular — created a sense of disarray not so much at the structural political level as at the doctrinal level within national societies. Henry Kissinger (1995) pointed out in his comprehensive study of diplomatic ties and political relations that the inter-war period was the undisputed consequence of tensions that had mounted during the First World War and had failed to be diffused by its outcome. More precisely, the collapse of the Russian Empire transformed Bolshevism and the concept of the social state into a full political doctrine: communism. On the German side, Nazism was on the rise, particularly because of the severe conditions Germany faced after the war, its economic containment, and its broadly enforced isolation from military and economic development. In Italy, the rise of Fascism — drawing on elements of both right- and left-wing doctrine — only added to a general European climate of extremism.

The Ideological Landscape: Communism, Nazism, and Fascism

Germany had suffered massively as a result of the First World War and its political leaders attributed that defeat to both military miscalculation and the political forces that had shaped it. The rise of Nazism — a right-wing political doctrine — was rooted in an impoverished society and a sense of historical injustice, particularly regarding France's control over economically vital territory such as the Ruhr region. Although a detailed account of the peace conditions imposed on Germany falls outside the scope of this paper, the political isolation exercised by the international community — and the League of Nations in particular — allowed Germany to develop a motivational political culture centered on economic recovery, social identity, and intolerance, which would eventually provide a basis for expanding German influence into the United Kingdom.

Russia, the successor state to the Tsarist Empire, had similarly developed a new doctrinal approach rooted in the need for economic recovery after the war. It should be noted that Russia, unlike other belligerents, withdrew from the conflict in 1917 as a result of the Bolshevik Revolution. That revolution marked the beginning of the end for most foreign influences within Russian territory and the emergence of the modern concept of the national state (Kissinger, 1995; Calvocoressi, 1994). The communist and socialist approach to foreign intervention was a forceful one, and the appeal of social equality was increasingly attractive not only to Russians but also to populations across the Balkans. However, from the initial beliefs of figures such as Lenin to what communism became under Stalin, the trajectory toward extremism was unmistakable.

Both Nazism and Communism originated, at their roots, as doctrines that claimed to serve their respective societies and to address the need for post-war reconstruction. Although both had genuine popular support — Adolf Hitler was elected by popular vote in 1933, while the Communist Party elected Josef Stalin as General Secretary in 1922 — their extremist trajectories diverged sharply from those original social foundations, and the propaganda apparatus of each regime drove the expansion of extremist principles throughout Europe.

Given this historical context, European countries — and the United Kingdom in particular — had pressing concerns about the spread of extremist forces across the Continent, especially a resurgent Germany and an increasingly assertive Russia. Russia's geographical and political distance from Western Europe made its brand of extremism a particularly unpredictable threat. The propaganda systems of both Germany and Russia aimed at promoting their respective doctrines domestically and abroad, making the role of intelligence and counter-intelligence all the more crucial.

The Role of MI5 and MI6 in British Counter-Intelligence

Anglo-Soviet relations after the First World War were essential for the British government, as Russia would have become genuinely unpredictable had no diplomatic contact been maintained. As Flory (1977, p. 707) notes, "The Bolshevik revolution in 1917 provoked hostility to the extent that the British intervened briefly on the side of the Whites during the civil war, but desire for trade led the Prime Minister, David Lloyd George, to extend de facto recognition to the Moscow regime in 1921 in the form of the Anglo-Soviet trade treaty. The first Labour Prime Minister, Ramsay MacDonald, went a step further, granting the U.S.S.R. de jure recognition in February 1924, although ambassadors were not exchanged." The British reaction to a resurgent Germany was similarly ambivalent. As Barros and Imlay (2009, p. 174) observe, "Convinced of Adolf Hitler's hegemonic ambitions, British decision makers recognized that Nazi Germany would eventually have to be confronted. The problem, however, was that Britain lacked the military capabilities to deter the Germans or, in the increasing likelihood that deterrence would fail, to wage and win a war." Despite this ambivalence, the British recognized the threats posed by both extremist political forces and, through MI5 and MI6, sought to counter the expansion of their political influence within the United Kingdom.

The Secret Intelligence Service (SIS) is the modern designation for MI6, the foreign arm of the British intelligence community. While MI6 is responsible for "gathering intelligence outside the UK in support of the government's security, defense, foreign and economic policies," MI5's mission is "protecting the UK, its citizens and interests, at home and overseas, against threats to national security" (SIS, 2014). The bureau that would become both agencies was established in 1909, with its creation prompted by Germany's military and naval expansion and widespread newspaper coverage of German espionage activity in Britain. Its dual tasks were to counter foreign espionage on British soil (the Home Section) and to collect secret intelligence abroad on Britain's potential enemies (the Foreign Section). The Home Section eventually became the Security Service (MI5) and the Foreign Section became the Secret Intelligence Service, or MI6 (Secret Intelligence Service MI6, 2014). The threats posed by both German and Russian intelligence and infiltration were therefore identified as concerns for British society even before the First World War.

The agencies' work focused heavily on countering German and Russian infiltration techniques, which included — among other methods — the recruitment of British students for espionage. Specialists regard this as one of the most significant means through which Russian intelligence gathered information and sought to influence British society, and it is also one of the first areas in which MI5 demonstrably fell short. As Thurlow (2004, p. 611) notes, "The obvious failure to monitor effectively the recruitment of secret communists at British universities highlighted the difference; in particular MI5 ignored early reports of communist cells in British universities. Although MI5 were vaguely aware of the presence of another 'great illegal,' Arnold Deutsch, in Britain during the 1930s, there was no conception of the sophistication of his recruitment propaganda, or the tradecraft on which his agents were trained."